GENERAL DESCRIPTION
Since the PWM and PFC circuits share the same oscillator, synchronization of the two stages is inherent. Special care has been taken in the design of the ML4819 to increase system noise immunity. The PFC section is of the peak current sensing boost type, using a current sense transformer or current sensing MOSFETs to non-dissipatively sense switch current. This gives the system overall efficiency over average current sensing control method. The PWM section includes cycle by cycle current limiting, precise duty cycle limiting for single ended converters, and slope compensation. FEATURES
s s s s s s s s s Two 1A peak current totem-pole output drivers Precision buffered 5V reference (±1%) Large oscillator amplitude for better noise immunity Precision duty cycle limit for PWM section Current input gain modulator improves noise immunity Programmable Ramp Compensation circuit Over-Voltage comparator helps prevent output “runaway” Wide common mode range in current sense co...
Micro Linear
